With the development of the display technology, liquid crystal display (LCD) and organic light emitting Diode (OLED) display have been widely used in various portable electronic devices as two mainstream display devices.
An OLED display comprises an organic light emitting diode pixel array and an organic light emitting pixel driving circuit driving each pixel. FIG. 1 shows a schematic diagram of an organic light emitting pixel driving circuit of existing technology.
As shown in FIG. 1, an organic light emitting pixel driving circuit includes an organic light emitting diode D1, a driving transistor DT, a storage capacitor C1, a first switching transistor T1, a second switching transistor T2, a data line Data, a scanning line S1, a light emitting control line EMIT, a first power source voltage terminal VDD and a second power source voltage terminal VEE.
The scanning line S1 first provides a low level signal. The first switching transistor T1 is turned on. The data voltage signal on the data line Data is written to a node N1, and held constant in one frame period by the storage capacitor C1. The light emitting control line EMIT then provides a low level signal. The second switching transistor T2 is turned on, and the organic light emitting diode D1 illuminates.
However, in the layout design of an OLED display panel using the existing technology, the metal layer in which the data line Data is located usually covers (or partially covers) the metal layer in which the gate of the driving transistor DT is located, and a row of pixels commonly share a single data line Data. The signal on the data line Data is constantly changing as the scanning line is switched (for example, from scanning the first line to scanning the second line), and a parasitic capacitance generated by a signal change on the data line Data acts on the gate of the driving transistor DT through an overlapping portion between two metal layers, which then affects the data voltage held by the storage capacitor C1, generating a crosstalk.
In view of the above defects and disadvantage in existing technology, it is desired to provide an organic light emitting pixel driving circuit, a driving method and an organic light emitting display panel to solve the technical problems in existing technology.